[Collada Export] Exporting with origins in Y-UP results in misalignment of mesh and skeleton + broken animations #98529

New Issue

Nooga · 2022-06-01T04:12:13+02:00

Nooga commented

2022-06-01 04:12:13 +02:00

System Information
Operating system: Windows 10
Graphics card: Nvidia GTX 1050 Ti

Blender Version
Tested on 2.79, 2.8, 2.9 and 3.1.2

Short description of error
Importing collada models with Y-Up origins (such as those exported from UE4 or Unity engines) and exporting them to collada, then reimporting them again will have severely broken animations in Blender, and in other programs such as 3DS Max and Blender 2.79 the skeleton will be rotated outside of the mesh. Models with the skeleton issue can be manually fixed by rotating the origins of the model by -90 degrees on the X-Axis so that the axes align with Blender's, but that does nothing to fix the animations (rigging is otherwise fine). Global orientation settings in export don't appear to do anything. Oddly enough, looking at the mesh in Noesis, the skeleton is aligned correctly but the animations are still broken, and are broken differently depending on if you fixed the origin alignment or not before exporting. Previously (2.9 and backwards) the skeleton issue could be seen there too.

(1) A Y-UP model

(2) Expected animation of that same model

(3) The same frame but after exporting and reimporting

(4) Original Y-UP model in Blender 2.79

(5) Exported (from 3.1.2, but this happens on other 2.8+ versions too. It also happens in 2.79, but only appears with the issue in 2.8+ if exported from 2.79) and reimported model in Blender 2.79

Exact steps for others to reproduce the error
(Note - the FBX, which was exported from AssetStudio, was converted to Collada via Noesis - may be relevant?)

Import a model with a Y-Up origin (See YUP_Original.dae)
Export that model to Collada format (Result should turn out like Export_YUP_Test.dae)
Reimport the newly exported Collada model into Blender 2.79, 3DS Max, etc - anything that isn't Blender 2.8 and forward
Animations will be broken no matter what program you import into, but the ones above should have a skeleton rotated 90 degrees out of the mesh

I've attached the original Y-UP collada exported from Noesis, the Y-UP exported from Blender, the "fixed" Z-Up exported from Blender, and the original FBX exported from Unity. Please let me know if there's any more info I can give to help.

**System Information** Operating system: Windows 10 Graphics card: Nvidia GTX 1050 Ti **Blender Version** Tested on 2.79, 2.8, 2.9 and 3.1.2 **Short description of error** Importing collada models with Y-Up origins (such as those exported from UE4 or Unity engines) and exporting them to collada, then reimporting them again will have severely broken animations in Blender, and in other programs such as 3DS Max and Blender 2.79 the skeleton will be rotated outside of the mesh. Models with the skeleton issue can be manually fixed by rotating the origins of the model by -90 degrees on the X-Axis so that the axes align with Blender's, but that does nothing to fix the animations (rigging is otherwise fine). Global orientation settings in export don't appear to do anything. Oddly enough, looking at the mesh in Noesis, the skeleton is aligned correctly but the animations are still broken, and are broken differently depending on if you fixed the origin alignment or not before exporting. Previously (2.9 and backwards) the skeleton issue could be seen there too. (1) A Y-UP model ![image.png](https://archive.blender.org/developer/F13125767/image.png) (2) Expected animation of that same model ![image.png](https://archive.blender.org/developer/F13125771/image.png) (3) The same frame but after exporting and reimporting ![image.png](https://archive.blender.org/developer/F13125776/image.png) (4) Original Y-UP model in Blender 2.79 ![image.png](https://archive.blender.org/developer/F13125780/image.png) (5) Exported (from 3.1.2, but this happens on other 2.8+ versions too. It also happens in 2.79, but only appears with the issue in 2.8+ if exported from 2.79) and reimported model in Blender 2.79 ![image.png](https://archive.blender.org/developer/F13125783/image.png) **Exact steps for others to reproduce the error** (Note - the FBX, which was exported from AssetStudio, was converted to Collada via Noesis - may be relevant?) 1) Import a model with a Y-Up origin (See YUP_Original.dae) 2) Export that model to Collada format (Result should turn out like Export_YUP_Test.dae) 3) Reimport the newly exported Collada model into Blender 2.79, 3DS Max, etc - anything that isn't Blender 2.8 and forward 4) Animations will be broken no matter what program you import into, but the ones above should have a skeleton rotated 90 degrees out of the mesh I've attached the original Y-UP collada exported from Noesis, the Y-UP exported from Blender, the "fixed" Z-Up exported from Blender, and the original FBX exported from Unity. Please let me know if there's any more info I can give to help. [M001_InBattle.fbx](https://archive.blender.org/developer/F13125798/M001_InBattle.fbx) [YUP_Original.dae](https://archive.blender.org/developer/F13125794/YUP_Original.dae) [Export_YUP_Test.dae](https://archive.blender.org/developer/F13125795/Export_YUP_Test.dae) [Export_ZUP_Test.dae](https://archive.blender.org/developer/F13125797/Export_ZUP_Test.dae)

Nooga commented

2022-06-01 04:12:13 +02:00

Added subscriber: @Nooga

Omar Emara commented

2022-06-06 15:18:03 +02:00

Added subscriber: @OmarEmaraDev

Omar Emara commented

2022-06-06 15:18:03 +02:00

Changed status from 'Needs Triage' to: 'Confirmed'

Omar Emara commented

2022-06-06 15:18:03 +02:00

I can confirm. But it would greatly help if you have a more simplified file for debugging this.

Nooga commented

2022-06-08 12:23:45 +02:00

In #98529#1369348, @OmarEmaraDev wrote:
I can confirm. But it would greatly help if you have a more simplified file for debugging this.

Hi Omar! Happy to oblige, but could you clarify what you mean by "simplified" in this case? Do you want a file with less bones? A humanoid shape? Please forgive my ignorance, first time reporting bugs here and the guide didn't really give any indication of what an "ideal" file looks like.

> In #98529#1369348, @OmarEmaraDev wrote: > I can confirm. But it would greatly help if you have a more simplified file for debugging this. Hi Omar! Happy to oblige, but could you clarify what you mean by "simplified" in this case? Do you want a file with less bones? A humanoid shape? Please forgive my ignorance, first time reporting bugs here and the guide didn't really give any indication of what an "ideal" file looks like.

Omar Emara commented

2022-06-08 12:37:49 +02:00

@Nooga Just a file with less bones, shorter animations, and simpler objects. The ideal file would just be a cube with as little bones and animations as possible, while also showing the issue clearly. I know this can be hard to create, so it is not absolutely necessary, just helpful to have.

Germano Cavalcante referenced this issue

2023-12-11 16:58:54 +01:00

incorrect bone offset causes dae animation corruption #115969

Sign in to join this conversation.

No Label

Download

What's New

Blender Studio

Manual

Developers Blog

Documentation

Benchmark

Blender Conference

Development Fund

One-time Donations

[Collada Export] Exporting with origins in Y-UP results in misalignment of mesh and skeleton + broken animations #98529